How to stretch youtube video window to screen width?

Question

YouTube

Previously, the extension for youtube Magic Actions for YouTube™ , due to the cinema option, Allowed you to watch videos through java "as if" in full screen, the tab did not collapse, but looked something like this:

Red arrows indicated that the video was full screen width, while in Unlike today's html5, which by default hides everything "unnecessary" , there was (and still is) the ability to hide everything separately, leaving only what you need displayed

In the last screenshot, I highlighted where, in my opinion, there was an option that allows you to make the optimal width fit the width of the screen. The main thing is that, unlike today's html5, the playlist system worked fine there. Help improve the resolution functionality of Magic Actions for YouTube™ so that there are no black bars around the edges and the entire working area of ​​the screen is used as efficiently as possible ( like here ), or tell me how to make Html5 on YouTube normally switch from video to video in a playlist as when watching via JavaScript rather than stop after viewing the first one.

Answer 1

dulsky.eu/d/pT2UbN1AHo0=list=PL7ZR5aX0xMRxVlJiA3zKYNu2GHQyM1kzu Demo test.
So what? We write percentages or by clicking (with a script) we get what size you need.